If you can’t take a bloody nose, go home and crawl under your bed.
It’s not safe out here. It’s wondrous,
with treasures to satiate desires both subtle and gross…
but it’s not for the timid.
-Q

In my book, Death from the Skies!, I don’t spend much time discussing magnetars. Although terrifying — able to generate truly mind-numbing outbursts which I’ll describe in a moment — they are simply too rare and too far away to be much of a threat.

Yeah, well, I might’ve been wrong. A little wrong, I mean; there’s no reason to panic. Life on Earth won’t be snuffed out by some rogue magnetar blasting away our atmosphere or anything like that. But one of my main premises for feeling completely safe has been eroded a bit, and to be fair I should talk about it.

Magnetars are neutron stars, superdense balls of tightly packed neutrons left over from the collapsed core of a massive star that’s gone supernova. Neutron stars have about the mass of the Sun but are only a few kilometers across, making them fantastically dense and giving them surface gravities that can be billions of times the force you feel standing on the Earth. They also can possess magnetic fields literally trillions of times stronger than the Earth’s. And in some cases, young neutron stars can be even more powerful: their field strength might be a quadrillion (1,000,000,000,000,000) times the Earth’s! These beasts, called magnetars, probably lose that field strength rapidly, decaying in only a few thousand years. That makes them rare on a galactic scale.

Still, several are known to exist. And they can have a nasty, nasty temper.

See, the magnetic field is coupled to the crust of the neutron star. The crust is extremely rigid and under vast pressure from the gravity of the star. If the crust cracks — a starquake, if you will — the energy released makes the strongest earthquake ever recorded on our planet look like a friendly pat on the back. I once calculated the strength of such a starquake, and it would register as magnitude 32 on the Richter scale. This ultraviolent blast shakes the magnetic field of the star, which in turn reacts by slamming around subatomic particles… the bottom line is that such an event can trigger a phenomenal release of X-ray energy from the star. And by "phenomenal" I mean "pants-wetting terrifying".

In December 2004, the magnetar SGR 1806-20 underwent such a starquake. In one-tenth of a second the subsequent blast released something like 2 times 1046 ergs of energy — equal to about 50 trillion times the Sun’s output during that same period.

Holy crap.

This star sits about 50,000 light years from the Earth: literally halfway across the Milky Way galaxy from us. Yet, even from that forbidding distance, this titanic event was able to physically affect the Earth. It compressed our magnetic field and partially ionized our atmosphere, causing it to puff up measurably.

Mind you, it was 500 quadrillion kilometers (300 quadrillion miles) from us at the time.

So you can see why these things are a bit unnerving. But really, this one is so far away! Sure, it can hurt us, but at that distance really all it can do is what it did; we don’t expect it can have a bigger event, so we’re safe enough. Moreover, these objects are so bright in X-rays that we think we’ve found all the really big bruisers in the Galaxy. If one were closer to us, there’s no way to hide it. We’d see it.

Yeah, about that…

Astronomers have announced they found a new magnetar, named SGR 0501+4516, and it’s only 15,000 light years away. It turns out to be dark most of the time, emitting very little energy, which is how it escaped detection. But it had an outburst last year that lasted four months, allowing scientists time detect it and to get a good long look at it. This event was far less violent than the one from SGR 1806 in 2004, but still nothing to sneeze at.

Is it capable of an SGR 1806-like event? Probably not — that was an extraordinary event — and I certainly hope not! At 1/3 the distance, the effects on Earth would be nine times as strong. That could damage satellites and possibly even cause some effects on Earth itself — probably nothing that would be too big a deal, but still. Yikes.

The thing is, in Death from the Skies!, I said we’re safe from these things because they’re far away, and it’s not possible to hide any closer to us. Yet here is this one, three times closer than SGR 1806. It makes me wonder if there are any closer still. If one were, say, 5000 light years away and had a blast like the one in 2004, the effects would be 100 times larger! There could be serious satellite damage, and possibly even blackouts on Earth due to electric currents induced in our power grid.

Let me be clear: I seriously doubt there’s anything that close to us. This new one at 15,000 light years is something of a fluke, and it’s entirely possible it’s not capable of the same kind of explosive event as its more distant cousin. The odds of one being even closer are pretty small, so I’m not too concerned about it. If I were, believe me, I’d let you know!

The point here is that we have to be careful when we talk in absolutes, and it’s always good to question assumptions. If there’s one thing we know for sure about the Universe, it’s that it’s capable of some pretty good surprises, and not all of them need be the happy fun kind. We’re almost certainly safe from this particular threat… but maybe a little kick in the complacency isn’t always such a bad thing.

OK, dumb question. What’s a magnetar made of? I’m always hearing about how incredibly dense a neutron star is. I’m familiar with the periodic table. Always thought that, aside from the extreme upper elements that we’re able to create in colliders, it pretty much ended at plutonium or thereabouts, correct? So what elements make up the crust of a neutron star? Impossilbe to know? Any theories? Or does normal elemental science just curl up in a ball, suck its thumb and cry for its Mama cause none of the usual rules apply?

I think it is funny how the article mentions that “if a magnetar were to magically appear at half the Moon’s distance from Earth, its magnetic field would wipe the details off every credit card on Earth.” As if our credit cards would be our main concern with one of these terrifying beasts that close to us…

@Brian: I could be wrong, but I believe the “curl in a ball, suck its thumb, and cry for Mama” idea is the correct one there. Neutron stars, from what I understand, as just big balls of highly condensed neutrons (neutral sub-atomic particles). Its about as dense as matter can get before it goes black hole.

Phil, you said that the magnetar which caused the 2004 event sits at about 50,000 light years from us. I have often wondered about the relation between a stellar event and the time it takes to reach us. Since X-ray is also light, am I correct to assume that the event actually happened 50,000 thousand years ago? Or does X-ray have a different speed from conventional light (if there is even such a term)? How do astronomers figure out the distances of the stars?

In December 2004, the magnetar SGR 1806-20 underwent such a starquake. In one-tenth of a second the subsequent blast released something like 2 times 10^46 ergs of energy — equal to about 50 trillion times the Sun’s output during that same period.

From a large-number perspective, I found this to be overwhelming. So I did my own calculations, and found that the magnetar’s energy output in that one-tenth of a second is equal to the sun’s total output since we decided to come down from the trees and start walking a bit more upright (approx. 158,000 years ago).

Edit: scratch that – maybe it was more around the time we started using tools. Someone help me out here.

Neutron stars are formed when high mass stars create iron in the core. Iron can’t fusion nor fission, so there’s no way for the core to produce energy and thus balance the inward force of gravity by the outward force of thermal and radiative pressure. So the core collapses due to gravity and reaches a point where it’s so dense that electrons and protons are forced together to form neutrons. That process releases huge amounts of neutrinos which trigger the supernova explosion that blows away the outer layers.

The core of now neutrons keeps collapsing. If neutron degeneracy pressure is enough to stop gravity, you get a neutron star. Neutron degeneracy pressure is due to the quantum mechanics and the fact that neutrons don’t like to have the exact same energy (in a similar way that electrons don’t).

There has to be some charges still left on the magnetar in order to create the magnetic field as magnetic fields are created by moving charges.

In regards to Magnetars – great name aside – could Magnetar activity / explosive events cause mass extinctions? While meteor-impact evidence does exist for some extinctions (like the 75 million year ago dino wipeout) – what would be the effect on Earth-life if something huge happened not so far away?

@StoneAge Scientist: X-rays are light and travel the same speed as visible light, so yeah, that burst originated ~50,000 years ago.

@Carey: Upright walking started around 3.7 million years ago. Stone tool use came up around 2.5 million years ago. We were already walking our way out of Africa and into Eastern Asia by 1-2 million years ago. Only 158,000 years ago we were pretty close to being anatomically modern humans

Now you’ve just triggered an apocalypse greater than anything a magnetar could accomplish.

Expect to see unleashed, a barrage of bad movies on the Family Channel and Fox about the world about to be destroyed by a magnetar. Expect to see Clint Eastwood come out of retirement again as John Glenn, aided by Brad Pitt, Keanu Reeves and Liv Tyler, to fire a nuclear missile from the Space Shuttle …… You can guess the rest.

I think you need to release a second, revised edition of Death From The Skies… which, BTW, I will be picking up from the local bookstore here in Squamish, tomorrow!

And by “phenomenal” I mean “pants-wetting terrifying”.
Umm, well I hate to break it to you, but for me it’s “pants-crappingly” terrifying… Do you have any suggestions on how to remove the brown stain from my pants, or should I just send you the bill

In all seriousness, this is truly mind blowing, that we live in a Universe where such forces even exist! I think this is beyond our comprehension in many ways. It’s hard to imagine that an object 50,000 LY away can have a physical effect upon the Earth!

@Strahlungsamt: A movie about stopping some invisible X-rays from irradiating the entire planet from a bazillion miles away would be… Oh, wait – the Magnetar has taken form! Brad Pitt just climbed down it’s mouth and is trying to lasso it back to the evil place it came!

My Inbox now has a new mail that says: “Run nowhere, a NASA scientist just posted in his Blog that a magnetar close to us is about to explode! Forget about Nibiru, Herculubus and Mars… this star is real! And the Blog is from Discovery MAgazine”

Ok… maybe it is time for write a Fe de Errata for your book and start sending copies to all of us that have your book.

Heh… I love it. My next 365 Days podcast is about magnetars; when I produced it a month ago, this new one hadn’t yet been announced… cool beans!

What is so interesting about these things is that they were first detected decades ago, but at the time we didn’t have the cool techno stuff we do now for monitoring these babies. The truth is, there are likely lots of these guys out there… and, the good news (if such thing can be good) is that many of them are weaker than the big one halfway across the galaxy, and more are like the new one — sorta weak and not so blustery. They tend to “wear down” after a while…

A few details regarding Neutron stars. The outer portion of the star is a mix of neutrons , ions, atomic nuclei, and protons. This region is fairly thin, perhaps a kilometer or two. The name Neutron Star is a bit misleading, as these stars are not made up completely of neutrons. In fact, if they were, they would not have a magnetic field, which requires some sort of conductivity. So, you have to have something other than just neutrons. The University of Oregon has a good, brief tutorial here: http://physics.uoregon.edu/~soper/NeutronStars/neutronstars.html. There is a longer, and much more detailed article on Wikipedia.

OK, dumb question. What’s a magnetar made of? I’m always hearing about how incredibly dense a neutron star is. I’m familiar with the periodic table. Always thought that, aside from the extreme upper elements that we’re able to create in colliders, it pretty much ended at plutonium or thereabouts, correct? So what elements make up the crust of a neutron star? Impossilbe to know? Any theories? Or does normal elemental science just curl up in a ball, suck its thumb and cry for its Mama cause none of the usual rules apply?

This is not such a dumb question if you’ve never read much about neutron stars.

The intense gravitational pressure that forms a neutron star is actually larger than the electron degeneracy pressure that supports, say, a white dwarf (neutron stars are typically more massive than white dwarfs). It’s a bit more complicated than this in reality, but go and read DftS for a bit more detail about how a supernova forms something really, really dense.

Anyhow, once the force is strong enough, it forces the electrons to combine with protons and form neutrons. Thus, most of the matter in a neutron star is a degenerate sea of neutrons. With almost no protons and no electrons, normal chemistry does not happen. The crust of a neutron star will typically be iron.

Iron can’t fusion nor fission, so there’s no way for the core to produce energy and thus balance the inward force of gravity by the outward force of thermal and radiative pressure.

This isn’t quite true.

Iron can fuse (otherwise, how could we ever have Cobalt, Nickel, Copper, Zinc, Gallium, Germanium, Arsenic, Selenium, Bromine, Krypton, Rubidium, Strontium, Yttrium, Zirconium, Niobium, Molybdenum etc. etc.?). However, in so doing it takes in energy rather than emitting energy. This is why elements heavier than iron are only ever made by supernovae – the intense shock waves that pass through the material during the supernova explosion are able to compress it for just long enough to force some of the iron to fuse into heavier elements. It also explains why these heavier elements are so much rarer than the lighter ones.

Any more news on the threat posed by that Wolf Rayet potential gamma ray supernova burster? The one the BA posted about ages ago – last year or before if memory serves ..
What was it called … WR-104 I think? Some sort of binary with a weird spiral shape flowing off from it… right?

Which is a worse threat, BA, this new magnetar or that W type star from last year?

@ 16 Michael L :

” It’s hard to imagine that an object 50,000 LY away can have a physical effect upon the Earth!”

Didn’t you read Phil’s book where he talked about the Andromeda Galaxy – Messier 31 -which will actually collide with our own Galaxy and perhaps eject our whole solar system or even sling it into the Milky Way’s central supermassive black hole? That’s even further away at 2 million light years distant … at least it is for now!

Mind you, M31 is a whole galaxy bigger than our own not just a city-sized stellar corpse …

(As they said on an ep of The Simpsons – DMY : Don’t Mess Yourself, Michael L. , not again! )

Look, I might not be one of you big-city astrophysicists, but in my day (ca. 1998-2000) I was a fully licensed* Pokemon trainer, and upon dusting off my old Pokedex, I discovered that Magnetons (which you repeatedly mispell as “magnetars”), while powerful in their own right, are at best capable of city-wide havoc – not global [see http://en.wikipedia.org/wiki/List_of_Pok%C3%A9mon_(81-100)#Magneton ]. Just the kind of scaremongering I’d expect from a LIBERAL BLOGGER.

This is why elements heavier than iron are only ever made by supernovae – the intense shock waves that pass through the material during the supernova explosion are able to compress it for just long enough to force some of the iron to fuse into heavier elements. It also explains why these heavier elements are so much rarer than the lighter ones.

Bzzt! You forgot the words “naturally made” there – humans have created other elements artificially in labs, incl. one just recently made for the first time …

Good post otherwise, I just think its worth mentioning that we humans can already beat the cosmos at the elemental (NOT element~ary!) nucleosynthesis creation game when it comes to substances like Americum, Einsteinium, Berkellium , etc .. 8)

Incidentally, I wish the BA had posted on that news (new artificial element) too or did I just miss it?

This whole business is not really a joking matter, but I can’t help but laugh a little when you use the term outburst. I can only picture the magnetar out there throwing a little tantrum like a 2-year-old to get attention.

When you say that “I seriously doubt there’s anything that close to us” I am assuming that you are basing this upon:

1. the rarity of Magnetars,

2. the fact that they arise from Supernovae as a form of Neutron Star, and

3. given their origins, their distribution would not be homogeneous but -rather- more densely clustered towards the older stars in the Milky Way and not really, necessarily, near us.

Is this correct?

If so, the smaller example 15,000 Light Years from us: what effects do you think it has had on our planet in the past? Has anyone done any geologic research to see if it has left any “fingerprints” behind? Or would it be so weak (even at its relatively close distance) that it wouldn’t be able to do so?

?
Free electrons may flow across the surface of neutronium, thus the magnetic field generation is maintained and the surface could be MOSTLY neutronium. For all I know, neutronium might even act as a surface super conductor.

GAry 7
PS: Some recent calculations of neutronium indicates it would have to have about one billion times the tensile/stiffness of steel,,,wow! What a cool construction material. I wonder if it would remain in a collapsed state if removed from the G field of its source star?

Understanding what a neutron star is made of is, to say the least, a very tricky business. The equation of state (that is, the mathematical relationship between fundamental quantities such as density, pressure, temperature, etc.) is way, WAY outside what we can test in the lab. Add to the fact that in such strongly curved spacetime it’s all deep into the nonlinear analytical morass of General Relativity, and you have a real stinker of a physics problem on your hands. Consider, for example, just the complication that arises from the fact that the way the neutrons are arranged won’t even correspond to the sort of closest packing of spheres rules that we are used to in Euclidean (flat space) geometry.

So, ask a half dozen neutron star wonks what the density of a neutron star is, and you might get six (or more) answers.

But if SGR 1806-20 was a minor 2.0 – 2.9 on the Plait magnetar scale (analogous to the Richter scale: “Generally not felt, but recorded.”), then SGR 0501+4516 can at most be a 3.0 – 3.9 (“Often felt, but rarely causes damage”) and the hypothetical close magnetar a light 4.0-4.9 (“Noticeable shaking of indoor items, rattling noises. Significant damage unlikely”).

I can’t seem to be even a *little* frightened for unlikely damage, even if global. (I.e. it isn’t just me that can get a piece of the roof in my head, it will be all of us.) But anyway I will probably be scared by the shaking furniture when it actually happens.

maybe it was more around the time we started using tools. Someone help me out here.

Delighted to. Well, already australopithecines are believed to move quite well as bipeds ~ 4 Ma, both from skeletal traits and several famous sets of footprints (“Laetoli footprints”). It is debated if they were obligate (aka “always” or “preferably”, I think) bipeds, but in any case the functional ability predated a consistent tool culture.

As it happens, a consistent tool culture seems to be the “fossil trait” that defines humans as Homo for anthropologists. Other apes, birds, et cetera uses tools, but adopts them by social learning (from “aping” others), not communicative learning, which may explain why these tool cultures don’t persist. Likely they don’t spread efficiently enough, which is consistent with the localized cultures observed. Homo habilis, the first consistent tool culture ape, is ~ 2.5 Ma.

Your ~ 0.2 Ma was indeed roughly when H. sapiens sapiens burst onto the scene. ~ 0.5 Ma is when neanderthal and sapiens diverged. (I.e. that is the approximate date of the last common ancestor, whoever he was, based on both DNA and fossils.) While I don’t think there are any widely held traits that identifies sapiens as such nor can it be due to this time gap in the record, both fossil morphology and DNA has been used to differentiate between the two known groups.

Personally I (a layman) don’t see any truly dramatic functional difference, AFAIU now they even have found traces of the probably same type of “voice box”. Except possibly that humans matured faster – we probably survived because we outbreed our competitors/bad environment. [Speaking of a *little* frightened, IIRC DNA analysis says we, for some reason or other, survived a bottle neck with efficiently a mere ~ 2000 sapiens. Maybe it was then our predilection for early sex maturation was established.] The tool cultures differ more, as I understand it – IIRC no arrows et cetera among neanderthal.

I’m not astronomer, but based on Phil Plaits information it would require a Magnetar to be pretty close to due some serious damage to life on earth. I’m not against excluding external distant events from causing a mass extinction but in the history of life on earth most mass extinctions where gradual events (at the behest of provoking perturbed professional paleontologists) sometimes assisted by a more local cosmic event (like really local). Death from the skies might cause some death but life on earth has a nasty habbit of killing itself off frequently in conjunction with geologic events on earth (example Permian-Triassiac event).

Based on what I’ve researched extra-solar events as possible causes of extinctions are that they are a fairly new concept and it’s hard to find evidence other than I suspect it would cause a sudden (in geologic terms) die off of life on earth. However, as good as life is at killing itself off, there is so much diversity that it springs back pretty quickly.

I personally put death by Magnetar well below the possibility of me accidently triggering a nuclear war by detonating a nuclear device I made from hundreds of fire alarms and some uranium ore

Ah, thanks. From the last thread on neutron stars IIRC the mechanism of magnetic field was raised but AFAIU not given a decided answer.

I see that I probably got the compression and frozen field correct, hasn’t bothered to check. However if the astrophysicists maintain that conductivity is needed then neutron star bulk matter must be paramagnetic instead of in the coupled ferromagnetic state I assumed was needed for a frozen field. (Had forgotten all about conducting liquid magnetic field trapping. D’oh!)

That makes sense, as these stars can be assumed still hot by contraction and what not, at least in the beginning. “The temperature inside a newly formed neutron star is from around 10^11 to 10^12 Kelvin.” [Wikipedia.] Yikes, that is hot!

In the face of the universe we are going to have to learn to impetuously nod our heads without consequently breaking our necks

I’m not sure I’m more afraid of the fact that someone working for Discovery mag knows about this and has not been hired by someone else yet.

Or

The fact that the writer doesn’t know we are all just trying to survive on every level every day even cosmically since year one. Honestly don’t worry about being fried, intrigue yourself with the glorious stars, that’s what they are there for.

But seriously?

If your going to burn in a “CATACLYSMIC DEATH STAR MATCH UP” you can only cease and desist? Correct? It’s not like anyone on Earth has the knowledge or power to stop anything cosmic.

See now, this is one of the reasons I like Science.
not the scary magnetar stuff (which is indeed cool stuff), but the fact that science corrects itself. Here we have noted astronomer Phil Plait saying : “Well, I was a bit wrong here. ”
Unlike the “other ways of knowing” where “The Troof” is set and damn anybody who disagrees, even if they have proof.

(nothing personal Phil… you were going with the best information available at the time. )

“Good post otherwise, I just think its worth mentioning that we humans can already beat the cosmos at the elemental (NOT element~ary!) nucleosynthesis creation game when it comes to substances like Americum, Einsteinium, Berkellium , etc ..”

Just curious (I’m a mere engineer) – could these ‘man-made’ elements (and yet heavier elements) have occured naturally, perhaps in particularly violent regions of the universe? Is there any theoretical end to the periodic table, or could we keep fusing atoms till the cows come home making ever heavier elements, limited only by our ability to come up with decent element names?

An additional question. How would these magnetars affect the potential for life elsewhere in the universe? If your planet had the bad luck to form in the local (galactically speaking) area of one of these things, could it snuff out any chances of your planet forming an intelligent, civilized race? Would that be something to consider in terms of the search for an extraterrestrial intelligence or are the chances insanely low that this would happen?

@Liam,
At the risk of sounding like a complete ignoramus (I never even finished college), I believe that the huge, and ever increasing, amounts of energy required to get ever-heavier lumps of particles to form new elements runs into a roadblock as the required energy of fusion gets to be large enough to quarkify the elementary particles. Also, I seem to recall that there are certain ratios of protons to neutrons which are more stable, but even these are so violently radioactive that new elements exist in particle accelerators, and theoretically in the hearts of supernovae, only for fractions of moments.

So it was magnetic particles that “compressed our magnetic field and partially ionized our atmosphere, causing it to puff up measurably”, or some kind of plasma?

So this ‘stuff’ has been hurtling through space for 50,000 years? How wide a swath do you think it created? Do we have instruments that could image the path? It’s obviously pushed stuff out of the way in order to impact our magnetic field. Would taking measurements from both sides of Earth’s orbit help?

The solar system is moving at 251 km/s around the galaxy, so it’s traveled roughly (251*31,556,925*50000) 396,039,408,750,000 km or 244,468,770,833,333.33 miles or 41.86 light years just to get smacked by the magnetar.

I would think that Nature has indeed created all the same isotopes that Man has made in the lab. It’s just that the total supply of these elements, which all have very short half-lives, had decayed long before man arrived on the scene.

A lot of time has passed between the super-nova that created all the elements in our solar-system and now. Plenty of time for anything heavier than uranium to be down to its last three atoms by now.

(Please correct me if I’m wrong about that, especially if we do encounter “natural” elements heavier than uranium. I’d love to know more.)

On a different vein here, does anyone remember the movie The Fifth Element? I think the dead star depicted there as The Great Evil may have been a magnetar. As I remember it, the dead star was attracting satellites and probes magnetically from far away places and then absorbing these into its own.

Hmm, I wonder what Phil’s views are on The Fifth Element. Would love to know how bad he thinks the science of the movie is.

@Alan#61: Good question also. I’m still waiting for Phil to chime in and tell us what would happen if a Magnetaur exploded next to us (say, within a few thousand light years). I want to hear the doom and gloom of how my flesh will be torn off from me as I see giant magnets go into geocentric orbit.

If they are as dangerous / deadly as assumed, that means we’d have to take that into account when talking about how many possible civilizations or life there is elsewhere in the galaxy. We’d have to create “assumed deadzones” where carbon based or “Earth-like” life wouldn’t be able to form.

Bzzt! You forgot the words “naturally made” there – humans have created other elements artificially in labs, incl. one just recently made for the first time …

Good post otherwise, I just think its worth mentioning that we humans can already beat the cosmos at the elemental (NOT element~ary!) nucleosynthesis creation game when it comes to substances like Americum, Einsteinium, Berkellium , etc

Darn it. I meant to mention particle colliders and nuclear reactors, but my train of thought led me elsewhere before I had committed that thought to … erm … electrons.

Of course, plutonium was the first artificial element (wasn’t it first detected at the University of Chicago after they analysed the outcome of the first atomic pile?), but I think most of the actinides are artificial. Certainly the transuranics are. Well, unless you count the natural fission reactions that occurred a few million years ago in uranium deposits beneath Oklo.

Is there any theoretical end to the periodic table, or could we keep fusing atoms till the cows come home making ever heavier elements, limited only by our ability to come up with decent element names?

Well, practical issues aside, IIUC there are predicted to be “islands” of stability at certain numbers of neutrons & protons. So, rather than every new heavier element being so unstable it decays in nanoseconds, some of them may be stable. As in, perhaps as stable as 16O or 12C.

Transuranic elements? That reminds me of Sapphire & Steel, a short-lived British television series from the ’80s that was a bit Dr. Who mixed in with effective horror.

To this day, the pilot episode, where an entity that strived on nursery rhymes was unleashing its power, gives me the goosebumps; the episode that involved photographs was horrifying, too. (DVD set sits on my shelf.)

Larger stars are shorter lived, and there are plenty of them around. You don’t have to be -much- larger than the sun to make a supernova and a neutron star. I presume the risk of the supernova itself includes forming the magnetar, so that’s already on the books – I mean in The Book. Right?

And since we haven’t BEEN wiped out by X-rays in the last 4 billion years – assuming there aren’t any past inadequately explained mass extinctions I forgot – our local magnetars probably have behaved themselves.

(If there was mass extinction on just one hemisphere, and if it was the time of the one supercontinent, would that appear in the fossil record, or would animals and plants from outside the exterminated zone have moved in straight away, so that you couldn’t tell in the fossil record that anything happened? I mean, if you have a one decade time-lapse camera watching the World Trade Center… uh…. -really- bad example?!)

I suppose the problem with dating stuff that happened outside the Solar System is that it depends how far away the thing is and you don’t -know- that, necessarily. So putting it on a cosmic timeline as 55,000 years ago is liable to be revised. And that’s -before- you bring in relativity, and what if you went in a spaceship to the object at the speed of light while your twin brother stayed home… What you do know is when you saw it.

Another question here: how come that the speed of light is always constant no matter the distance it traverses? Since light is also a form of energy, shouldn’t this energy disperse (weaken, or slow down) as it travels farther out from its origin point (in this case, a star)?

“The point here is that we have to be careful when we talk in absolutes, and it’s always good to question assumptions.”

This is a principal difficulty in debate with Muggle…, I mean, non-scientific folk.

If you look around carefully, you will note that all proper observations include the method of observation, that all measurements have uncertainty factors, and that only standards are exact. “Exact” means a definition, with no uncertainty about it.

In short, there is no such thing as certainty other than by definition, a conceit of ours. You do not know where you came from, how you got here or where you’re going. You know you can fooled, sometimes in comic fashion by someone like Randi. You don’t even know how tall you are with the precision you routinely demand of companies you do business with. Don’t let your eyes and ego lie to you about things you must infer.

If you look at light as photons, the answer becomes clear: Picture individual photons all bursting out from a point source, in all directions. They will all keep on travelling at the same speed (c) until they hit something. But the distance between individual photons increases as they travel away from that point source. So the number of photons passing through a given area drops with the square of the distance from the source.

So that’s how light can keep travelling at the same speed, yet become weaker.

Or to put it another way: Light doesn’t get “tired” as it travels, it just disperses over a larger area.

62. Autumn:
Ignoramus means someone dedicated to NOT learning. As long as you’re trying, you’re not that,,,
College degrees are for one principle purpose, to provide accreditation attesting to the “fact” of ones education. A continuing pursuit of knowledge is the principle reason for libraries. Self education is the ideal,,,

69. Robert Carnegie:
As far as mass extinctions go, you might find the following link interesting,,,

Yes, I now understand how the distance between photons increases as they travel away from the point of origin. I was mulling over this when it occured to me that this is the underlying principle behind the dimming of light you’re talking about.

Still, I have to point out that when you wrote, “They will all keep on travelling at the same speed (c) until they hit something…,” it wasn’t at all clear why this was immediately a given constant. I can imagine a starship traversing space in constant light speed. But since photons have no propulsion drive, what makes an individual photon travel at uniform speed all throughout its journey in space? (Please bear my curiosity. Thanks)

I can imagine a starship traversing space in constant light speed. But since photons have no propulsion drive, what makes an individual photon travel at uniform speed all throughout its journey in space? (Please bear my curiosity. Thanks)

Nothing that has mass can be accelerated to light speed.

Photons are massless and, through a vacuum, will always travel at c whatever your frame of reference.

The reason that macroscopic objects usually slow down as they travel is because energy is being transferred from them to something else (e.g. if you take your foot off the gas pedal of your car, it will slow down, because it loses energy as heat to friction with the air, friction with the road and friction between internal moving parts).

However, light is quantised. A photon cannot transfer part of its energy to something else. It is an all-or-nothing affair. Either a photon is absorbed, or it is not, and continues travelling at c.

Now, photons do lose energy as they travel large distances, because their energy is related to wavelength, and their wavelength is stretched by the expansion of the universe as they travel (this is essentially the Doppler effect).

Yes, I see. This is indeed interesting, as it is enlightening. Intriguing, too, if I might add. I wonder how scientists visualise photons, as these have no mass at all, and yet still be considered as particles (yes, I did some sleuthing in Wikipedia). Isn’t this premise kind of paradoxical in itself?

That’s nothing. Wait till you get to the bit about light being both a particle and a wave, but really neither.

As to why c is the maximum, why it is the particular value it is, and why light travels at c and not something else: You’d need to go deeper into both Maxwell’s equations of electromagnetism and into special relativity than I ever have. I just take the expert’s word for it.

Dr. Paul Laviolette has been discussing the probability that such a star exists in the center of the Milky Way galaxy and erupts on a regular basis causing periodic ice ages on earth, among other effects.

Aaargh! I still have a lot of questions in mind. It seesms that questions appear ad infinitum.

Laymen questions like,
1. What happens to a photon when it totally loses energy? That would mean that there are a lot of inert (but moving) photons out there, right?
2. Since photons cannot transfer energy, as explained by Mr. Depledge, why is it we feel heat when touched by light?

I went and did some fats checking on this article…most of it is junk, calculations are made too sound way more than they really are. this is kinda like cnn news – take a little bit of fact and mix in a whole lot of technical jargon and put fear into people so they keep reading. worst article ever.

In the midst of all these back-and-forth comments about magnetars, I’m concerned that nobody has given proper credit to the two astrophysicists who coined the term and conceived that these objects exist. I’m referring to Rob Duncan and Chris Thompson, who met with tremendous skepticism from the astrophysics community when they first defined the physical properties of highly magnetic neutron stars. Their groundbreaking physics work gave younger scientists a leg up on their careers, but I very rarely see proper attribution or credit in the popular press.

So remember, when you think “magnetar,” think “Duncan, R., and Thompson, C.” It’s the decent thing to do.

To this day, the pilot episode, where an entity that strived on nursery rhymes was unleashing its power, gives me the goosebumps; the episode that involved photographs was horrifying, too. (DVD set sits on my shelf.)

Ooh, yes. “The transuranics are unstable and may not be used where there is life.”

That series was so cool. Plus, it had that really bizarrely chilling ending. Even more plus, it had Joanna Lumley playing Sapphire…